1. Field of the Invention
The present invention relates generally to a material testing instrument and, more particularly, to a system and method for identification of a detachable component of an instrument.
2. Background of the Invention
A rheometer is a device that measures stress and strain associated with a specimen or a test sample during material testing. TA Instruments Ltd, Leatherhead, Surrey, England, which is a subsidiary of TA Instruments, New Castle, Del., manufactures a number of rheometers, including Models AR 550, AR 1000, and AR 2000.
The AR 550 is a general purpose rheometer with many features of a research grade system. The AR 550 is an upgradeable system, which means it can be upgraded as its user's applications expand. A variation of the AR 550 is the QCR II that can be used to transfer Theological tests from a laboratory to a manufacturing facility or a quality control laboratory. The QCR II is a robust rheometer that easily automates the analysis of a broad range of samples.
The AR 1000 is a research grade rheometer incorporating a unique motor design and advanced material air bearing. It has excellent torque performance and very low inertia. The AR 1000 can be equipped with multiple temperature control options, a normal force sensor, and custom geometries.
The AR 2000 is currently the most advanced rheometer. Its innovative Mobius Drive™ offers unprecedented controlled strain and controlled stress performance. The AR 2000's unique features include its broad torque range, superior strain resolution, wide frequency range, and ingenious convenience features, like the Smart Swap™ interchangeable temperature control options.
FIG. 1 is a cut-a-way view of an AR 2000 rheometer. Rheometer 100 includes casting 110, optical encoder 120 (also known as a displacement transducer), motor and bearings assembly 130, measuring geometry 140, a temperature system (not shown) that is attached to rheometer 100 at mechanical magnetic coupling 150, and normal force transducer 160. The functionality of each of these components is generally known and is therefore not described herein.
The temperature system can be quickly attached to rheometer 100 at mechanical magnetic coupling 150. The information that identifies the temperature system to software of rheometer 100 is held in a programmable chip. The programmable chip is contained within the connector that plugs into socket 112 of casting 110. This connector also carries electrical signals and power to and from the temperature system.
A test sample is placed in measuring geometry 140. The test sample fills a gap between an upper measuring geometry and a lower measuring geometry. The lower geometry is not free to rotate and can, but not always, be part of the temperature control system. The upper member of measuring geometry 140 is connected to motor and bearings assembly 130. The lower member of measuring geometry 140 forms part of or is connected to the temperature system. When the test sample is placed within measuring geometry 140 and rheometer 100 is activated, the various properties of the test sample can be measured or otherwise calculated by rheometer 100. For example, when motor and bearings assembly 130 applies a force on the test sample, the temperature system obtains the temperature of the test sample, and other components of rheometer 100 can determine other raw parameters of the test sample. The raw data include, for example, torque, displacement, speed, temperature, phase, gap, and the like, are used together with the measuring geometry information to calculate rheological parameters such as shear rate, shear stress, modulus, compliance, etc.
Depending on the nature and characteristic of the test sample, measuring geometry 140 can be one of several types of geometries. For example, measuring geometry 140 can be one of cone-and-plate, plate-and-plate, concentric-cylinders, and torsion type geometries. Each type of measuring geometry is associated with a unique set of characteristics, information, or data. For example, a measuring geometry can be associated with, among other properties, a diameter, a cone angle, an inertia, and other information or data that is unique to the measuring geometry. In the case of cones type measuring geometry, each cone is associated with unique calibrated data.
Accordingly, it is important that correct information associated with the measuring geometry is used by the software or firmware of rheometer 100 to calculate rheological parameters of the test sample from the raw data. If the wrong measuring geometry file is selected in the software or the wrong dimensions are entered by a user, then when the sample measurement is carried out the results can be erroneous. Known problems or disadvantages associated with manual entry include operator error (in terms of geometry selection and parameter input) and the time required to select or setup a geometry. Thus, there is a need for a system and method that would eliminate or reduce operator errors at least in terms of geometry selection and parameter input, and to reduce the time required to select or setup a geometry. Circle 180 shown in FIG. 1 indicates the portion of rheometer 100 in which the present invention can be embodied.